1. Field of the Invention
This invention is directed to the production of an antitumor antibiotic designated herein as BMY-41219 and to a process for the preparation, isolation and purification of BMY-41219.
2. Background Art
U.S. Pat. Nos. 4,487,925 and 4,552,842 disclose the anti-tumor agent designated rebeccamycin, and the 5'-methyl and 5', 2', 3", 6"-tetraacetate derivatives thereof, and a process for producing the same agent by cultivating a rebeccamycin-producing strain of Nocardia aerocolonigenes, preferably Nocardia aerocolonigenes ATCC 39243, or a rebeccamycin-producing mutant thereof in an aqueous nutrient medium containing assimilable sources of carbon and nitrogen under submerged aerobic conditions until a substantial amount of rebeccamycin is produced. Recently Nocardia aerocolonigenes ATCC 39243 was reclassified as Saccharothrix aerocolonigenes ATCC 39243 (Bush et al., J. Antibiotics 40: 668-678, 1987).
It was found that when the rebeccamycin-producing culture was supplemented with L-tryptophan, the production of a minor analog of rebeccamycin was significantly enhanced. This analog of rebeccamycin was subsequently isolated and designated as BMY-41219.